Push To Talk (PTT) over Cellular (PoC) is a new service being deployed in cellular networks. One of the intrinsic values of PTT communications is rapid (“instant”) call setup. Nextel, using iDEN technology, has made Direct Connect (PTT) the cornerstone of their unique service offerings. However, to date, most implementations of PoC have suffered from very long access delays, thus making the communications anything but “instant”.
Most PoC implementations take the approach of transporting the voice over packet data channels. Packet data service in systems such as the Global System for Mobile communications (GSM) and the Universal Mobile Telecommunications System (UMTS) is governed by the notion of Packet Data Protocol (PDP) contexts. The PDP context defines the IP address and the Quality of Service (QoS) class for a data session. UMTS defines four distinct QoS classes: background, interactive, streaming and conversational. Interactive class QoS is appropriate for the signalling portion of PoC service, while streaming or conversational QoS is preferred for the audio portion of PoC due to their tighter transfer delay requirements. However, establishing a streaming or conversational media PDP context can add significantly to the call setup delay.
Thus, what is needed is a method and apparatus for managing PDP contexts that meets QoS requirements for the PoC conversation while simultaneously reducing the impact on access delay. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.